Trigger mechanism



Aug. 25, 1964 Filed July 11, 1963 E. L. MORROW TRIGGER MECHANISM 5 Sheets-Sheet 1 A 7' TORNEY Aug. 25, 1964 E. L. MORROW TRIGGER MECHANISM 5 Sheets-Sheet 2 Filed July 11, 1963 INVENTOR EDIWl/PD L. MORROW KJ ATTORNEY Aug. 25, 1964 E. L. MORROW TRIGGER MECHANISM Filed July 11,-- 1965 5 Sheets-Sheet 3 INVENTOR. EDWARD L. MOP/POW KL/M ATTORNEY Aug. 25, 1964 E. MORROW TRIGGER MECHANISM 5 Sheets-Sheet 4 Filed July 11, 1963 INVENTOR EDWARD L. MGR/POW ATTORNEY 5, 1964 E. 1.. MQRRQW 3,145,496

TRIGGER MECHANISM Filed July 11, 1963 5 Sheets-Sheet 5 INVENTOR. EDWARD L. MORROW A T TO/PNEY 3,145,496 TRIGGER MECHANISM Edward L. Morrow, Fairfield, Court, assignor to Olin Mathieson Chemical Corporation, a corporation of Virginia Filed July 11, 1963, Ser. No. 294,441 4 Claims. (CI. 4269) The present invention is directed to firearms and in particular to firearms trigger mechanisms.

The trigger mechanism disclosed herein is an improvement upon the mechanism disclosed in US. Patent 2,922,241 issued January 26, 1960 to Lawrence J. Brunelle.

The Brunelle patent deals with a trigger mechanism embracing a movable sensing element for detecting the open or closed position of a firearms bolt; a sear is movably mounted on the sensing element and the trigger member is rendered inoperative depending upon the open or closed condition of the bolt signalled by the sensing element.

In certain firearms actions fitted with a sensing ele ment, such as the so-called slide action or pump gun, it frequently occurs that the shooter actuates the action (opens the bolt, extracts and ejects a spent cartridge, chambers a new load, returns the bolt to its closed position) and then tends to pull rearwardly on the forearm placing pressure upon the forward end of the sensing element prior to releasing the trigger from its fired position.

If the shooter pulls rearwardly on the forearm after operating the action and prior to releasing the trigger, the pressure on the sensing element develops suflicient friction between the sensing element and the bolt means, which it ordinarily contacts, to prevent movement of the sensing element.

This occurrence is undesirable and prevents return of the trigger finger piece to its released position even after the shooter has removed his finger.

For purposes of the present specification, the released position of the finger piece is that position in which it is ready to release or unlatch a cocked hammer.

correspondingly, the fired position of the trigger finger piece is intended to denote the end of the stroke through which the finger piece is rotated in firing the gun.

As is apparent in said U.S. Patent 2,922,241, the sensing element is intended to detect the open or closed position of the bolt, thus designating the safe or unsafe condition of the bolt.

Of course, it is anticipated that the sensing element may detect the open or closed condition of the bolt by contacting the bolt directly or by contacting an instrumentality associated with the bolt where the position of said instrumentality indicates the open or closed position of the bolt.

Accordingly, it is a particular feature of the present invention to provide a trigger mechanism including a bolt sensing element operative to permit the trigger finger piece to return to its released position after the sensing element has signalled a closed bolt even though the shooter is pulling rearwardly on the forearm with sufficient force to block movement of the sensing element.

Another feature of the present invention is the provision of a novel trigger mechanism including a movable sensing element in combination with a bolt means, a hammer, a sear, a trigger finger piece and means providing a lost motion connection between the sear and the sensing element.

It is a further feature of the invention to provide cam means for positively moving the sensing element clear of a blocking position With respect to bolt means Where the cam means is actuated in response to operation of the hammer.

A trigger device embracing certain features of the present invention may comprise a frame member, a ham- 3,1454% Patented Aug. 25,, 1964:

mer means movably mounted in said frame member, said hammer means being movable from a cocked position to a fired position, a sensing element pivoted in said frame, a sear movably carried by said sensing element, said sensing element being movable from an operative position in which the sear is operative to an inoperative position in which the sear is inoperative, and cooperating cam means formed integral with the hammer means and with said sensing element efiective to render the sear inoperative when the hammer means moves from the cocked position to the fire position.

An additional exemplary trigger device embracing certain other features of the present invention may include a frame for supporting a hammer, a trigger, a sear and a sensing element, said sear being operative to latch the hammer in a cocked position, said trigger cooperating with the sear to unlatch the hammer, bracket means for supporting the sear carried by the sensing element, said bracket means and said sensing element being movable relative to one another, said bracket means and said sensing element each having a position relative to one another and relative to the frame defining a firing position, said trigger being inoperative to actuate the sear to unlatch the hammer unless both the bracket means and the sensing element are each disposed in the firing position.

Other features and advantages of the present invention will become more apparent from the succeeding specification when considered in conjunction with the appended drawings in which:

FIG. 1 is an elevational view, with certain portions broken away, showing a typical firearm action in which the present invention is useful;

FIG. 2 is a view similar to FIG. 1, somewhat enlarged, showing a slide action firearm cocked and ready to fire;

FIG. 3 is a similar view showing a slide action after firing and with the trigger fully released;

FIG. 4 shows the action cocked, however, the action is inoperative because the trigger is still held in its fired position in which it was placed during firing of a previous round; and,

FIG. 5 is an exploded view showing the configuration of the sensing element, sear bracket, sear and hammer pin.

Referring now to the drawings and in particular to FIG. 1, the reference numeral 10 designates a receiver. Trigger guard 11 including frame 12 is secured to the receiver by means of pins 13 and 14. Trigger 16 having a finger piece 17 and a sear actuating stud 18 is pivoted to the frame 12 by means of the pin 19. Sear 21, pivotally mounted to sear bracket 22, is powered by spring 23 tending to drive the sear 21 in a clockwise direction about sear pivot pin 24. Motion of the sear relative to bracket 22 is limited by the engagement of tail 26 with the rear wall 27 of the sear bracket as is most apparent in FIG. 5.

Referring now to FIGS. 2, 3, and 4, it is apparent that sear bracket 22 is pivotally mounted to a sensing element 29 by means of pin 31. The pin 31 also serves to mount the sensing element 29 to frame member 12.

A'hammer means including a hammer 32 rigidly fixed to hammer pin 33 is supported in frame 12 by the pin 33. Spring 34 drives the hammer tending to move the hammer clockwise as viewed in FIGS. 1-4 to actuate firing pin 36 of bolt means indicated generally by the reference numeral 37.

Details of the sensing element 29, sear bracket 22,

sear 21 and hammer pin 33 are apparent in FIG. 5. Note that the sensing element 29 includes a manually operated arm 38, cam slot 39, sensing head 41 and bracket stop 42. Hammer pin 33, which is rigidly fixed to hammer 32 so that there is no relative motion, includes a cam 43 which cooperates with camslot39 to actuate the sensing element 29 in a manner which will become more apparent hereinafter.

Sear bracket 22 includes a rear wall 27 and arm 44. Arm 44 is formed with a shoulder 46 which cooperates with stop 42 of the sensing element 29 to limit upward travel of the sear bracket 22. correspondingly, arm 44 includes a stop 47 which cooperates with the frame 12 (see FIG. 3) to limit the downward motion of the sear bracket 22.

The sear bracket 22 is carried by the sensing element by means of pin 31. Correspondingly, sear 2 1 is pivotally supported in the sear bracket 22 by means of pin 24. The sensing element 29 is normally urged counterclockwise by spring 49, most apparent in FIGS 2 and 3. Sear bracket 22 is normally urged clockwise to the position shown in FIG. 3 by the power generated by spring 23. Specifically, spring 23 tends to rotate sear 21 clockwise about pin 24 and the contact between sear tail 26 and bracket wall 27 drives sear bracket means 22 in a clockwise direction about pin 31. The tail -1 of spring 23 which bears on the trigger 16 is operative to urge the trigger counterclockwise about pin 19v to retain trigger finger piece 17 normally in the released position as shown in FIGS. '2 and 3.

The operation of the present inventionoccurs as follows:

Referring to FIG. 2, assume that .the action disclosed is cocked and ready to fire and the sensing element 29 is signalling safe condition of the bolt means 37.

Note that the sensing head 41 of the sensing element 29 is in its uppermost position indicating thatfthe =bolt means is fully closed.

Note that the bolt slide 52 of the bolt means 37 is in blocking relationship with respect to the sensing head 41. The upward motion (counterclockwise motion about pin 31) of the sensing element 29 islimited by the engagement of cam slot 39 with the cam cut-out 43 of hammer pin 33. The sensing element is in the firing position. The hammer 32 is latched by sear 21 and trigger lug 18 is in operative contact with shoulder 53 of the sear. Although the normal position of the sear bracket 22 is the position shown in FIG. 3, the dominance of hammer spring 34, whose influence is transmitted through sear 21, is operativeto rotate the sear bracket counterclockwise to bring'shoulder 46 into contact with stop member 42. The scar bracket is in the firing posit-ion.

Upon actuation of the trigger by pulling the finger piece 17 to the left as viewed in FIGS. 2 and 3, sear '21 is rotated counterclockwise to unlatch the hammer so that the hammer sharply strikes the firing pin 36 to assume the position shown in FIG. 3. Cooperation between the cam 'slot 39 and the cam 43 is effective to drive the sensing head 41 of the sensing element 29 downwardly to the position shown in FIG. 3. Upon releaseof the trigger finger piece 17, reciprocation of the forearm 55 (see FIG. 1) will recock the hammer in well known fashion and if'the bolt meansis returned fully to its closed position the piece parts of FIG. 3 will return to the arrangement shown in FIG. 2 ready for firing a second time.

Note in FIG. 3 that the rear end 54 of the bolt slide 52 is tapered or beveled to lead the slide over the head of the sensing element. Y j

A reference to FIG. 4 Will'disclose further operation 7 of-the present invention emphasizing the utility of the lost motion connection between the sear 21 and the sensing element 29 provided by the. sear bracket 22. I

Assume that the representation of the trigger elements disclosed in FIG. 4 illustratesthe disposition of the trigger mechanism piece parts immediately after a load has been 7 I fired and after the action has been pumped with the bolt fully closed and the sensing element signalling a closed bolt; g a a The additional circumstances are that (1) the shooter has not yet released the trigger from the previous firing -and;(2) the shooter is pulling rearwardly'on his forearm 55 (see FIG. 1) causing the bolt means 37, in particular bolt slide 52, to assume the position shown in FIG. 4.

The bolt slide 52 is being hauled rearwardly with sufficient pressure to prevent rotational movement of the sensing element 29 about its pivot pin 31.

Note that since the trigger finger piece 17 has not been released, trigger lug 18 is not in an operative position relative to the sear 21 (compare with trigger lug and sear of FIG. 2). in its fired position, the lug 18 .of the trigger does not engage shoulder 53 on the sear and the sear is blocked.

Note further that sear bracket 22, specifically the arm 44 thereof, is poised approximately midway between its uppermost (firing) position and lowermost (normal) position. I

With the trigger mechanism in the condition just described and as illustrated in FIG. 4, release of the trigger finger piece 17 will unblock the sear in that the lug 18 will'drop downwardly and slide off the flat 50 while the sear bracket will be urged to its firing position under the influence of dominant hammer spring 34. The sear will rotate slightly in a counterclockwise direction with the result that trigger lug 18 and sear shoulder 53 and sear bracket arm 44 will assume the position shown in FIG. 2. This isafiring position.

Were it not for the lost motion connection between the sensing element 29 and the sear '21 afiorded by the sear bracket '22, it would be impossible to fire the mecha- ,member, .a hammer means rotatably mounted in said frame member, said hammer means being movable from a cocked position to a fired position, a sensing element pivoted in said frame and a sear carried by said sensing element, said sensing element being movable from an operative position in which the sear is operative to an inoperative position in which. the sear is inoperative, and cooperating cam means formed integral with the hammer means and said sensing element effective to render said sear inoperative when the hammer means moves from the cocked position tothe fired position.

a 2. A trigger assembly comprising a frame for supporting a hammer, a trigger, a sear, and a sensing element, said sear being operative tolatch the hammer in a cocked position and said trigger cooperating with the searefiective to actuate the sear to unlatch the hammer, sear supportingmeans carried by the sensing element, said means and said sensing element being movable relative'to one another and eachhaving a position relative to one another and relative to the frame defining a. firing position, said trigger being inoperative to actuate the sear to un latch the hammer unless both the sear supporting means and the sensing element are disposed in the firing position.

a, 3. The assembly. of claim 2 wherein the sear supporting means comprises a bracket pivotally mounted to the sensingelement, cooperating means. onv the bracket and sens ng element for limiting motion of the bracket relative to the sensing element, said sear being operable to move relativeto the sensing element, the frame and the bracket. 7 l V 4. The device'of claim 2,. above wherein the sear is carried by a bracket member in turn carried by the sensing element operative to providea lost motion connectio between the sear and the sensing element.

No references. cited.

If the trigger finger piece 17 is retained 

1. A TRIGGER ASSEMBLY FOR A FIREARM COMPRISING A FRAME MEMBER, A HAMMER MEANS ROTATABLY MOUNTED IN SAID FRAME MEMBER, SAID HAMMER MEANS BEING MOVABLE FROM A COCKED POSITION TO A FIRED POSITION, A SENSING ELEMENT PIVOTED IN SAID FRAME AND A SEAR CARRIED BY SAID SENSING ELEMENT, SAID SENSING ELEMENT BEING MOVABLE FROM AN OPERATIVE POSITION IN WHICH THE SEAR IS OPERATIVE TO AN INOPERATIVE POSITION IN WHICH THE SEAR IS INOPERATIVE, AND COOPERATING CAM MEANS FORMED INTEGRAL WITH THE HAMMER MEANS AND SAID SENSING ELEMENT EFFECTIVE TO RENDER SAID SEAR INOPERATIVE WHEN THE HAMMER MEANS MOVES FROM THE COCKED POSITIONED TO THE FIRED POSITION. 